Glowplug light stays on

[Eugene]

Newb here with A2 1.6TD
My glowplug light sometimes comes on.
After startup and running for awhile, the light will start to faintly glow.
Sometimes it will come full on and even flash. It doesn't do it all the time only every so often.
I've drained the water separator underneath and at the fuel filter, and added fuel conditioner.
Could the glowplugs need replacing?

[hillfolk'r]

im wonderin if the water in fuel  sensor is goin bad,,,,,or some power /ground issue in the glow plug /water sensor circuit,,,

[ajt3nc]

My jetta started doing that and I went through the seperator, ground and usual suspects.
It ended up being water was coming in through the hood release cable and dripping on the fuse box. The glow plug relay was corroded.

[Eugene]

The relay is fine.
Where is the water in fuel sensor?

[LeeG]

The water trap underneath the car in right rear seat area has a water sensor built in.  You have to drop the trap to get to it, I'm not sure how servicable it is, I recently bought a spare trap that I plan to take apart to see.  My glowplug light flickers too.

If you want to disconnect that water sensor, inside the trunk, right front corner on the floor there is an access to the fuel tank, the sensor wires come through that with the disconnect inside the trunk just ahead of the access panel, under a piece of foam.  You dont need to take the acccess panel off.
At least that is where my '91 jetta has it.

[A Guy]

I had this problem and posted here a month or two ago.  I was told to drain the water from the fuel filter under the right rear side of the car.  I did this and the light operates normally now.
out.